He was the son of Sir Richard de la Vache, a well-to-do Buckinghamshire landowner who had acquired estates in Chalfont St Giles and Aston Clinton.
On 15 May 1388 he was appointed captain of the castle of Calais and in 1390 he negotiated a truce with king of France, count of Flanders and the cities of Ghent, Bruges and Ypres.
A country gentleman with a reputation for lavish hospitality, he may also have been the model for the Franklin in the General Prologue to "The Canterbury Tales".
In the First Book of Kings in the Old Testament, the cows on their way to Beth Shemesh are likened to holy men, or monks on their way to the Heavenly Jerusalem.
Chaucer may have regarded this interpretation of his name as a summons to give up his sinful life and to join the monks of Westminster Abbey.